The present invention generally relates to emergency oxygen supply systems such as are routinely carried on commercial aircraft for deployment upon loss of cabin pressure. More particularly, the invention pertains to an aircraft lavatory oxygen source to be used in the event of a decompression, to prevent an effect known as hypoxia.
Emergency oxygen supply systems are commonly installed on aircraft for the purpose of supplying oxygen to passengers upon loss of cabin pressure at altitudes above about 10,000 feet. Such systems typically include a face mask adapted to fit over the mouth and nose which is released from an overhead storage compartment when needed. Supplemental oxygen delivered by the mask increases the level of blood oxygen saturation in the mask user beyond what would be experienced if ambient air were breathed at the prevailing cabin pressure altitude condition. The flow of oxygen provided thereby is calculated to be sufficient to sustain all passengers until cabin pressure is reestablished or until a lower, safer altitude can be reached.
Passenger aircraft have typically provided passenger cabin areas as well as passenger lavatories with an oxygen supply with emergency oxygen masks that drop down to provide oxygen to passengers in the event of decompression of the aircraft at high altitudes. One conventional system for supplying oxygen to an aircraft cabin is known that includes a plurality of chemical oxygen generators with igniters and sequencers for energizing the igniters in sequence, and oxygen masks to which the chemical generators distribute the oxygen generated. A pressure sensor in part of the distribution system controls the sequencers to energize the igniter of the next chemical generator in sequence whenever the pressure drops below a threshold. Another conventional system for supplying emergency oxygen for passengers in aircraft is known that includes a mounting container that accommodates at least one breathing mask and an exothermic chemical oxygen generator connected to the breathing mask.
However, for certain passenger-carrying transport category airplanes with a passenger capacity of 20 or more, the Federal Aviation Authority (FAA) recently required either activating all chemical oxygen generators in the lavatories of the aircraft until the generator oxygen supply is expended, or removing the oxygen generators, and removing or re-stowing the oxygen masks and closing the mask dispenser door in the lavatories after the generator is expended or removed, to eliminate a potential hazard from placement of the chemical oxygen generators in the aircraft lavatories. Flight attendants are currently being instructed to check if lavatories are occupied in when a cabin depressurization occurs, to attempt to provide assistance to any occupants of the lavatories in quickly obtaining emergency oxygen. However, locking of lavatory doors by lavatory occupants and collapsing of lavatory occupants during such a cabin depressurization incident can potentially at least interfere with the rendering of assistance in obtaining emergency oxygen to lavatory occupants by flight attendants.
More recently, however, upon further review, the FAA required installation of an alternative supplemental oxygen system in each lavatory. It would therefore be desirable to provide a lavatory oxygen system to provide an aircraft lavatory oxygen source for such a supplemental oxygen system, in order to comply with current FAA requirements, in order to supply gaseous oxygen via a calibrated flow port. The present invention meets these and other needs.